Are you sure it was standard or "long" and not "large"? Standard pins are .154" in diameter, but Colt in their infinite wisdom produced proprietary pins that were tagged "Large" at .171"

There are anti walk pins that have been seen to be too "long" for some lower receivers. There was a set of pins that I got one time, and the "C" clip pin was a little long and caused a wobble. I don't remember the brand, but I think they were from Brownells.

I haven't run across a situation where a longer than average pin was specifically needed.

I just realized that I have a problem because I have a trigger out of a Colt with the .171" pins and installed it in my JDM lower with .154" pins. Do I need a new trigger?

I believe Colt's bigger pin size were for the Takedown and Pivot pins, effectively making it impossible for you to assemble an "other" lower and slap a Colt upper on it.

I am not a Colt expert (or fan ) so I can't say for certain but I do believe that they only did this on those two pins, for a short period in production time, and that it did not effect your other pins.

As such I believe you are good to go Viking - you can always check and see if the trigger has any slop to it. If you shake the lower and it rattles like a baby toy, you have a problem.

I just realized that I have a problem because I have a trigger out of a Colt with the .171" pins and installed it in my JDM lower with .154" pins. Do I need a new trigger?

If the hammer/trigger pins are the large size they won't slide in a milspec stripped receiver. If they did fit you must have .154"pins from a fairly new or very old Colt.

ETA:
If you used small pins on the large hammer and trigger to make them fit then yes you have a problem.

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The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
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US Army 1966-69, VFW Life Member, Retired Geek

BTW, Colt went to the large pins before the 1994 AWB hoping to distinguish its commercial ARs from military/LE. Their argument was the large pin "sporter" models would not accept triggers and uppers from "evil" ARs. Didn't work of course and caused needless headaches. They went back to milspec size after the ban sunset.

__________________
______
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
________________________________________
US Army 1966-69, VFW Life Member, Retired Geek